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%I #12 Oct 18 2018 16:51:51
%S 1,1,0,1,1,0,1,2,1,0,1,2,5,1,0,1,2,8,8,1,0,1,2,9,19,13,1,0,1,2,9,27,
%T 42,18,1,0,1,2,9,30,74,78,25,1,0,1,2,9,31,95,168,139,32,1,0,1,2,9,31,
%U 105,248,363,224,41,1,0,1,2,9,31,108,300,614,703,350,50,1,0
%N Number A(n,k) of factorizations of m^n into exactly k factors, where m is a product of two distinct primes; square array A(n,k), n>=0, k>=0, read by antidiagonals.
%H Alois P. Heinz, <a href="/A277239/b277239.txt">Antidiagonals n = 0..45, flattened</a>
%e Square array A(n,k) begins:
%e 1, 1, 1, 1, 1, 1, 1, 1, 1, ...
%e 0, 1, 2, 2, 2, 2, 2, 2, 2, ...
%e 0, 1, 5, 8, 9, 9, 9, 9, 9, ...
%e 0, 1, 8, 19, 27, 30, 31, 31, 31, ...
%e 0, 1, 13, 42, 74, 95, 105, 108, 109, ...
%e 0, 1, 18, 78, 168, 248, 300, 325, 335, ...
%e 0, 1, 25, 139, 363, 614, 814, 938, 1002, ...
%e 0, 1, 32, 224, 703, 1367, 1996, 2457, 2741, ...
%e 0, 1, 41, 350, 1297, 2879, 4642, 6128, 7168, ...
%Y Columns k=0-10 give: A000007, A000012, A000982(n+1), A101427, A277240, A277241, A277242, A277243, A277244, A277245, A277246.
%Y Main diagonal gives A254686.
%Y A(n,2n) gives A002774.
%K nonn,tabl
%O 0,8
%A _Alois P. Heinz_, Oct 06 2016
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